Answer:
280 g Al₂O₃
Explanation:
To find the mass, you need to multiply the given value by the molar mass. This will cause the conversion because the molar mass exists as a ratio; technically, the ratio states that there are 101.96 grams per every 1 mole Al₂O₃. It is important to arrange the ratio in a way that allows for the cancellation of units. In this case, the desired unit (grams) should be in the numerator. The final answer should have 2 sig figs to reflect the given value (2.7 mol).
Molar Mass (Al₂O₃): 101.96 g/mol
2.7 moles Al₂O₃ 101.96 g
------------------------ x ------------------- = 275 g Al₂O₃ = 280 g Al₂O₃
1 mole
The answer is 1.5*10^-12 square meters. For a detailed calculation, please refer to the attachment.
Answer: 7.98 grams of 
are produced if 10.7 grams of 
are reacted.
Explanation:
To calculate the number of moles, we use the equation:
.....(1)
Putting values in equation 1, we get:
The chemical equation for the reaction is
By Stoichiometry of the reaction:
2 moles of produce = 1 mole of
So, 0.100 moles of produce= 
of
Mass of =
Hence 7.98 grams of are produced if 10.7 grams of are reacted.
Answer:
C. Solid
Explanation:
It's most about the kinetic energy, when molecules have the least amount of room to move around, they have the least amount of energy.
For example if you think about gas and how spread out the molecules are in order to evaporate, there it the highest amount of energy there.
The molarity of HBr solution is 0.239 M
calculation
write the equation for reaction
that is LiOH +HBr → LiBr +H20
find the moles of LiOH used
moles =molarity x volume
=0.205 x 29.15 = 5.976 moles
by use of mole ratio between LiOH :HBr which is 1:1 the moles of HBr is therefore= 5.976 moles
Molarity of HCL= moles /volume
= 5.976/25 = 0.239 M
